The invention relates generally to automatic drain systems and more particularly to such drain systems for fuel processing apparatus for diesel and other types of engines.
In the past, when diesel fuel and other hydrocarbon fuels were plentiful and relatively inexpensive, there were significantly fewer problems with the quality of the fuel because of the substantial competition between sellers of the fuel. Refineries, distributors, and retailers were careful to keep water out of the fuel, and they usually did not pump out the heavy settlings from the bottom of the fuel storage tanks. In more recent times, however, because of shortages of oil and other factors, fuel suppliers can readily sell essentially all of their available oil with little difficulty. Also, in the past, kerosene and other fuels with lower cloud and pour points were blended with diesel fuel to facilitate cold weather flow and use. Fuel allocations due to government regulations, oil shortages, and other factors have now made it almost impossible to continue this practice. The result of these developments has been a distinct tendency toward lower quality fuel containing substantially more impurities, such as water, waxes, heavier compounds and particulate materials, which are very disruptive to the proper operation and starting of a diesel engine. Thus, one important object of this invention is to provide a new and improved fuel processor apparatus particularly for diesel trucks and other diesel-powered automotive vehicles to remove water and other impurities from the diesel fuel and to provide improved means for draining the water or other impurities from the processor apparatus.
An improved fuel processor apparatus broadly includes a fluid-tight chamber or canister through which the fuel flows and in which water and other impurities are separated in a lower portion of the chamber or cannister. In accordance with the invention, sensing apparatus is located in the lower portion of the chamber for detecting the presence of a predetermined quantity of water or other impurities, and a drain device is actuable, either manually or preferably automatically, in response to detection of said predetermined quantity to discharge at least a substantial portion of the water or other impurities in order to maintain them at or below said predetermined quantity. In a preferred form of the invention, automatic control means is provided for automatically actuating the drain device in response to detection of said predetermined quantity and for automatically deactuating the drain device in response to detection of a second lower quantity of such water or other impurities. In such preferred form of the invention, the quantity of water or other impurities is maintained generally between said predetermined and second quantities in order to substantially ensure that fuel is not discharged when the drain device is actuated. A temperature sensing means is preferably included for sensing the temperature in the lower portion of the chamber and is operative with the control means for automatically disabling the drain device, thereby preventing actuation of the drain device to discharge water and/or other impurities if the temperature in the lower chamber portion is below a predetermined temperature level.
Additional objects, advantages and features of the present invention will become apparent from the following description and the appended claims, taken in conjunction with the accompanying drawings.